Synthesis of Out-of-Substrate Au-Ag Nanoplates with Enhanced Stability for Catalysis

摘要

Metal nanoparticles represent an important class of components in many applications, such as catalysis, electronics, optics, optoelectronics, sensing, and data storage, because of their unique properties. In principle, the properties of a nanoparticle are determined by various parameters including composition, size, morphology, crystallinity, and surrounding environment, among which morphological control is one of the most powerful means to tune the properties and thus to influence the performance of the nanoparticle in different applications. For example, cubic silver nanoparticles bounded with {100} facets exhibit much higher catalytic capability towards the oxidation of styrene with tert-butyl hydroperoxide than silver nanoplates mainly bounded with {111} facets. Therefore, synthesizing metal nanoparticles with well-controlled shapes and well-defined crystalline surfaces becomes critical to enhance their performance in the envisioned applications. An additional challenge is to form stable assemblies of the as-synthesized nanoparticles to expose useful surfaces that are as large as possible.